This invention relates to photographic systems and more particularly, it concerns improved apparatus for accommodating modified format sizes of photographic sheet film in existing camera systems.
In the camera system marketed by Polaroid Corporation under the trademarks "POLAROID SX-70 LAND CAMERA" and "POLAROID SX-70 LAND FILM," camera structure and operation are integrated with a container or pack film in the sense that electric power for camera operation is supplied by a battery packaged with each film pack, a main power switch is closed upon full insertion of the film pack to connect the battery with camera carried electric circuitry, and the film container defines the location and to some extent the format area of an image to be formed on the uppermost of successive film units in the container. Each film unit in the system carries a supply of processing fluid in an amount calibrated to cover the image format area after exposure and passage of the sheet assembly between a motor driving processing roller pair supported in the camera. In particular, the processing fluid is spread across the interface between a pair of plastic sheets in each unit, at least one of which plastic sheets is transparent for exposure of a light sensitive layer carried between the sheets and so that the resulting positive photographic image may be viewed.
In the operation of the syste, the uppermost film unit in the container is exposed and then engaged at its rear edge (the top edge of the resulting photograph) by a linearly driven pack and advanced through a slot in the front wall of the container for a distance calibrated to place the leading edge of the exposed film sheet (the bottom edge of the photograph) within the nip of the processing roller pair. The roller then feed the exposed film unit forwardly to first rupture the processing fluid pod, spread the processing fluid across the interface between the plastic sheets and finally discharge the exposed and processed unit from the camera.
The battery supplied with each pack of the presently available "POLAROID SX-70 LAND FILM" is of a rectangular sheet-like configuration with dimensions approximating those of the individual film units. The terminals of the battery are presented in a lower face thereof to be accessible through appropriate openings in the bottom wall of the film pack container. The power storage capacity of the presently used battery is, moreover, much greater than that necessary to operate the camera for the exposure and processing of the number of film units contained in the film pack with which the battery is supplied. The excess of power stored in the battery is by design and to assure full power operation of the camera with each film pack as well as to provide the battery with a shelf life compatible with that of the film.
In a commonly owned and co-pending application Ser. No. 902,064, filed May 2, 1978 by John J. Driscoll et al, there is disclosed an accessory by which the existing "POLAROID SX-70 LAND CAMERA" is adapted to expose and process a small format (e.g., 35 or 45 mm format) film units prepacked in a modified container complementing the reduced size of the film units. The accessory disclosed is in the nature of a U-shaped housing having exterior planar dimensions complementing the interior planar dimensions of the standard film pack receiving well in the camera. The housing defines a forwardly opening recess of a size to receive and position the modified film pack and is otherwise equipped to retain the functional coaction of the standard film pack with the camera in terms of electric switch actuation and the like.
The disclosure of the aforementioned co-pending application further contemplates the incorporation of a sheet-like battery with each of the modified film packs cooperable with the disclosed accessory. In modestly reduced format sizes of film units such as a 45 mm format, the combination of film unit location and area represented thereby may permit the use of a modified battery positioned in the bottom of the reduced film pack container to be provided with planar terminals overlying the existing battery terminal contacts in the camera. Otherwise, the battery is accommodated by a peripheral flange-like extension of the modified film pack container about a lower edge thereof.